Tag Archives: Transit

The future of Metro’s rolling stock – ideas for the 8000 series

At some point in 2014, WMATA’s newest rail cars, the 7000 series, will enter service. These cars will depart from the same basic design of all of Metro’s current rolling stock in a couple of ways. However, despite the accolades of the new designs from Metro, the 7000 series design misses some key opportunities to squeeze extra capacity out of the system and run the trains more efficiently.

While the ship has sailed for the 7000 series, all is not lost. WMATA will need to eventually expand the fleet and replace the remaining older rail cars; and will do so with the yet-to-be-designed 8000 series. (WMATA current has four cars with 8000-level numbers from the 1000-series, comprising the money train.) Depending on the source, design work on the 8000 series could start between 2018 and 2020; the lead time for developing a new rail car is long; note this article on the 7000 series (again, set to enter service in late 2014) dated from January, 2008.

The 7000 series has potential to improve reliability and operate efficiently: WMATA’s contract holds the builder to meet or exceed a standard of an average of 150,000 miles between failures (WMATA’s current fleet achieves just over 60,000 miles between failures; 150k represents an improvement, but still shy of NYC’s fleet average, yet alone the performance of NYC’s newest railcars).

Efficient and reliable systems will be an important improvement, but they don’t address some of the broader elements of a good rapid transit system. With an eye towards improving the 8000 series, and after riding modern rolling stock in other cities around the world, I’ll offer some suggestions for future railcars in DC.

Maximize the number of doors: While riding Line 1 of the Paris Metro under crush loads, one thing that amazed me was the consistently short station dwell times. As a train pulled into a station, large numbers of people would board and disembark within a matter of 10-15 seconds, and then the train was on its way. Contrast that against WMATA during peak hours at one of the key transfer stations (Metro Center, L’Enfant Plaza, or Gallery Place): I’ve often seen train operators start to close the doors after 20-30 seconds, but people were still getting off of the car, to say nothing of those waiting to get on.

Metro’s current rolling stock features only three doors on each side of a 75-foot long rail car (New York gets four doors to fit on a 60-foot long rail car; Toronto’s new cars feature four doors on a 76 foot long car) Increasing the number of doors on each train makes the exchange of passengers from train to platform easier and faster, particularly with large crowds. The added ease also improves the reliability and consistency of station dwell times. Wider doors are also an option; the MP-05 trains in Paris operating on Line 1 feature three sets of wide doors per side of each 50-foot long rail car.

Paris Metro MP-05 train with wide doors. Note the lack of a cab due to fully automatic operation. CC Image from Wiki.

Paris Metro MP-05 train with wide doors. Note the lack of a cab due to fully automatic operation. CC Image from Wiki.

Despite pleading from train operators, when the dwell times are not long enough for passengers to board/alight, they will hold doors open. This introduces the potential for delay, both by degrading WMATA’s schedule adherence, but also by risking a door malfunction that will take the train out of service. WMATA’s procurement documents for the 7000 series sought a “proven linear door drive system” to improve reliability; however, changing the system’s design (by adding more doors) has the opportunity to improve efficiency and reliability above and beyond the technical systems.

Open gangways: More doors improves passenger flow between the train and platform; removing the doors within the train allows passengers to move along the entire length of the train. This increases capacity and improves the passenger experience, allowing them to naturally balance the load and move along the train if one car is too crowded.

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Looking through the open gangway of new S-stock in London, and at the floorplate in the gangway going around a curve. Photos by the author. 

The most compelling reason is additional capacity. In Toronto, the new ‘Rocket’ subway cars increased capacity by 8-10 percent. London’s new Sub-surface rolling stock features open gangways between cars, as does the MP-05 stock in Paris. New York is considering open gangways for future railcar procurements.

When asked about why the 7000 series did not include open gangways, Metro cited vague concerns about safety where a suspect might roam throughout the entire train. Yet, in New York, politicians have cited the inability to move between cars as a threat to safety. Both arguments rest on dubious assumptions, but appeals to a vague sense of safety cannot trump the obvious boost of an additional 10% capacity.

Seating arrangements: During discussions about the 7000 series, WMATA opted to keep the current seating arrangement, dominated by forward/rear facing seats, rather than sideways-facing seats that maximize standing room. In WMATA’s own mock-ups, the loss of seated capacity is minimal (about 8 seats per married pair, or 4 seats per car on average). While bench-style seating is common in Europe, is is not used exclusively – though all of the newer railcars make a strong effort to increase standing room and improve passenger flow within the car.

Interior layout of MP-05. CC image from Wiki.

Interior layout of MP-05. CC image from Wiki.

For example, consider the option of using forward/rear facing seats as singles instead of doubles. WMATA’s transverse seating is usually arranged 2+2, with a fairly narrow aisle. The MP-05 rolling stock in Paris uses a 2+1 combination, in addition to substantial center-facing seating. London’s S-Stock offers a variety of options, as does Toronto’s Rocket. Extensive use of flip-down seating adds flexibility for a variety of users, offering seats when necessary, but providing additional standing room during peak hours.

Passenger information: One of the most obvious improvements for passengers on WMATA’s 7000 series will be “next stop” displays (noted for the prototype’s typos), similar to the ‘FIND’ system in some of New York’s subway cars. These displays offer a strip map of the line, showing the next stations. However, more is possible. In Paris, the digital displays in the MP-05s not only display the upcoming stations, but the time to the end of the line, as well as major upcoming transfer points.

Above-the-door strip map for Line 8 in the Paris Metro. Photo by the author.

Above-the-door strip map for Line 8 in the Paris Metro. Photo by the author.

Digital displays offer flexibility to the operator to use trains on any line. However, many operators nonetheless use old-fashioned, route-specific strip maps.

Even though it’s not a subway or rapid transit application, the in-train displays from the Netherlands are impressive. The screens show the current route, next stops, scheduled arrival time and track. When arriving at a station, the in-train displays will show platform information for connection trains, allowing passengers to head directly to that platform. In the event of a delay or change in the schedule, the displays update immediately.

Blurry photo of info screen inside an NS InterCity train, with arrival and connection information. Photo by the author.

Blurry photo of info screen inside an NS InterCity train, with arrival and connection information. Photo by the author.

Overall: I’ll note that none of these are new or unique ideas; Matt Johnson (open gangways; more doors) and David Alpert (transverse seating) both suggested similar changes for the 7000 series. I’ve offered suggestions in the past, as well.

Toronto Rocket technical drawing. Image from Bombardier.

Toronto Rocket technical drawing. Image from Bombardier.

You don’t even need to look overseas to see many of these ideas in action. As mentioned above, Toronto’s new Rocket subway cars incorporate most of these ideas. WMATA has the same opportunities. Toronto’s Rockets feature permanently married 6-car trainsets (the maximum length for Toronto’s system), four doors per 76-foot long car, and lots of standing room without removing all transverse seating – something to aspire to for WMATA’s next railcar procurement.

Just returned from visiting Europe…

Paris, 7th Arrondissement. Photo by author.

Paris, 7th Arrondissement. Photo by the author.

Over the past two weeks, my fiancee I had the opportunity to visit friends and family in Europe – my first trip in far too long. Our itinerary included London, Paris, Amsterdam, and Utrecht. I hope to include photos and observations on the cities and their transportation systems in several posts over the long Thanksgiving weekend. I’ll start with some general and quick observations here.

On public transit: As you might expect, this trip included lots of transit. In London, we made extensive use of the Underground, as well as the Gatwick Express upon departure. In the Netherlands, we made extensive use of the Nederlandse Spoorwegen rail system, mostly using the InterCity trains between our home base in Utrecht to Amsterdam, Rotterdam, and Schipol. In Paris, we used both Metro and RER, as well as RATP’s modern tramways – a chance to see the lessons of modern streetcars applied in person.

The networks are all impressive, as were the levels of service and efficiency. It’s difficult to get a true sense of how the systems work for regular riders on a day-to-day basis when you’re just visiting. For example, a local laughed at my admiration for the NS rail system (admittedly based on a small sample size), complaining about frequent delays and never-ending construction. The grass might always seem greener on the other side, but complaints from the locals aside – I’m pretty sure it actually is greener in this case.

On high-speed rail: We traveled to Paris via the Thalys high speed train, using NS to meet the Thalys in Rotterdam. This was my first experience on true high-speed rail (sorry, Amtrak). While our return journey was delayed in departing due to a previous malfunction fouling the schedule, the overall experience was excellent – easy integration with public transit on both ends of the journey, no hassles in boarding the train or accessing the platforms – just check the display for your track, and check on the platform for where exactly on the platform to stand:

On-platform display at Rotterdam Central, showing platform locations (letters) for first class and second class coaches for the Thalys high speed service to Paris. Photo my the author.

On-platform display at Rotterdam Central, showing platform locations (letters) for first class and second class coaches for the Thalys high speed service to Paris. Photo by the author.

On walking: Of all the places we visited, Paris was by far the most pedestrian-friendly. Between the ample pedestrian infrastructure (not necessarily at the expense of the cars, given the wide Hausmann streets) and the excellent, ped-friendly city-scape, travel via foot was easy. While London’s urban design is extraordinarily ped-friendly, far more of the street right-of-way is devoted to car uses. Addtionally, the traffic culture (perhaps some combination of legal and cultural reasons – or maybe just my failure to adjust to looking the other way when crossing the street) clearly prioritizes vehicular movements.

In the Netherlands, particularly in Utrecht, the threat to peaceful pedestrian strolling is not from cars, but from bikes. With narrow cartways along canals and amid old, medieval street grids, the mixing between cars, bikes, and pedestrians is amazing – but it doesn’t necessarily allow for the Parisian-kind of urban strolling.

On tall buildings:  There were lots of them. Didn’t seem to be a big deal.

More to come…

A visual survey of selected elevated rail viaducts: Part 6 – Hong Kong

Another iteration of the series on elevated rail – for more, read the prologuepart 1part 2part 3part 4 and part 5

Hong Kong: Hong Kong’s Mass Transit Railway sets the gold standard for efficient rail operations. The system operates at a profit, the governing corporation makes money not just on transportation, but on the associated real estate development. Developing areas around stations both ensures a critical mass of riders to support the line, but also provides MTR with the long-term financial benefit of owning the assets that benefit from the rail system they operate.

All of these factors make Hong Kong an interesting subject for study. Many of the newer additions to the transit system are largely elevated; and many of those lines run through urban environments with street geometries and traffic volumes not dissimilar to suburban arterial streets elsewhere.

Large portions of Hong Kong violate many of the principles for great pedestrian streets, yet still manage to serve large volumes of city dwellers. Many MTR stations include pedestrian bridges and full grade separation for adjacent roads, rails, and pedestrians:

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View near Ma On Shan MTR station in Hong Kong. Image from Google Maps.

Or, consider the massive pedestrian overpasses that traverse this large roundabout at the intersection of two highway-like arterial streets near the Tai Wai station:

Aerial of pedestrian overpasses near the Tai Wai station (top of image). Image from Google Maps.

Aerial of pedestrian overpasses near the Tai Wai station (top of image). Image from Google Maps.

The physical viaduct structures themselves make little effort to shrink into the landscape. The combination of large pre-cast concrete viaducts with high sound walls make for a fairly bulky aerial structure. This example is part of the Ma On Shan line near the Sha Tin Wai station in the Sha Tin district of Hong Kong’s New Territories.

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Elevated MTR rail near Sha Tin Wai Station, Hong Kong. Image from Google Maps.

The rail line runs alongside the roadway. The roadways themselves are hemmed in by numerous fences and barriers; in this case, a median fence prevents jaywalking while fences along the road edge protect bike parking, with a bike trail and sidewalk beyond.

Pedestrian access to Sha Tin Wai station. Image from Google Maps.

Pedestrian access to Sha Tin Wai station. Image from Google Maps.

Not all stations are surrounded with the wide roadways, but even on lower volume streets, fencing restricts ped movements to the crosswalks. In the distance, you can see a pedestrian bridge to provide ped access away from the intersection in the foreground. The pedestrian bridge ties directly into the station’s mezzanine level.

Street-facing retail spaces beneath the station mezzanine. Image from Google Maps.

Street-facing retail spaces beneath the station mezzanine. Image from Google Maps.

Towards the other end of the station, you find street-facing retail within the station building, tucked beneath the station’s mezzanine. The concept is similar to the re-use of such spaces in older systems, showing that you can make it work without the charming brick and stone viaducts. Also worth noting: the global reach of 7-Eleven knows no bounds.

This kind of in-station retail not only breaks up the facade of the station (compare it to the blank walls of a similarly designed station without the retail), but the retail revenue helps fund the system operations. Retail is not limited to street-level exterior storefronts, but also includes in-station retail.

Mezzanine level retail spaces in MTR's Kowloon Bay station. CC image from Wiki.

Mezzanine level retail spaces in MTR’s Kowloon Bay station. CC image from Wiki.

WMATA’s Silver Line stations in Tysons Corner might have similar opportunities. “Sand Box John” Cambron’s photos from the Silver Line construction shows the size of the Tyson’s Corner stations. In particular, the two stations aligned to the side of the roadway (McLean and Tysons Corner) feature massive station structures with lots of potential space for these kinds of retail uses; however, such uses will now be retrofits rather than actively planned opportunities.

The curb lanes adjacent to the station are devoted to bus operations. Bus shelters on the near side of the street (just out of the image) provide riders with a quick transfer to the rail system by ascending to the overpass and walking directly into the station mezzanine.

Stations aren’t the only opportunities for multiple uses of infrastructure; Hong Kong features several examples of development in the air rights above rail yards, such as this development above the rail yard near the Kowloon Bay station.

Air rights development above rail yard adjacent to Kowloon Bay MTR station. Image from Google Maps.

Air rights development above rail yard adjacent to Kowloon Bay MTR station. Image from Google Maps.

Air rights development over Kowloon Bay depot. CC image from Wiki.

Air rights development over Kowloon Bay depot. CC image from Wiki.

Scarcity of land and open space forces some creative uses for available space. The Chai Wan station, terminus for the MTR’s Island line, includes rooftop recreational space with a park and tennis courts:

Tennis courts built on the roof of the Chai Wan MTR station. Image from Google Maps.

Tennis courts built on the roof of the Chai Wan MTR station. Image from Google Maps.

The station includes ground level entrances and street-fronting retail (level 0), a mezzanine level with retail and ticketing (+1), the platform (+2) and rooftop recreational space (+3).

View towards Chai Wan station. Image from Google Maps.

View towards Chai Wan station. Image from Google Maps.

Chai Wan station. Image from Google Maps.

Chai Wan station. Image from Google Maps.

The station’s tail tracks weave under and through buildings and over narrow streets:

Chai Wan station tail tracks. Image from Google Maps.

Chai Wan station tail tracks. Image from Google Maps.

Table of contents:

Exporting success from Hong Kong’s MTR – rail transit plus development

Hong Kong at night. CC image from Diliff via Wikimedia Commons.

Hong Kong at night. CC image from Diliff via Wikimedia Commons.

If you were to pick a rail transit system to envy, it would be hard to pick one better than Hong Kong’s MTR. The system is known for extraordinary operating efficiency; both in terms of on-time performance (99.9%) and farebox recovery (186%). Intense development around rapid transit stations both provides a market of potential rail users and an investment opportunity for the MTR’s parent corporation.

The MTR corporation, in turn, is looking to export their expertise in efficient transit operations around the world. An article in the Wall Street Journal profiles MTR’s ambitions:

Hong Kong’s MTR Corp. 0066.HK -1.15% is taking its high standards abroad, bidding to run subways in Europe, Asia and Australia. If it wins just a few of the bids, it will become the biggest operator of metro systems in the world. Led by a New Yorker, the company is also considering other projects, including in Germany, another place that puts a high value on efficiency.

“MTR in Hong Kong is probably the best-run metro in the world, and that brand is what they bring with them,” said Nigel Harris, managing director at the Railway Consultancy Ltd., a U.K.-based firm.

The train operator, which exports even its trademark door chimes and train-service announcements, already runs lines in the Chinese cities of Beijing, Shenzhen and Hangzhou, as well as in Melbourne, London and Stockholm. It has been shortlisted to run a train line in Sydney and three more lines in London, including Crossrail, one of the biggest rail projects in the city in decades.

Just how exportable is MTR’s success? Purely operational measures (on-time performance) seem to present the strongest case, particularly with such inefficient operations elsewhere in the world. Financial measures (whether simple metrics like farebox recovery or broader measures of profitability of the entire corporation) depend on the context of the system – not all cities have Hong Kong’s kind of density to support efficient transit. Planning metrics depend on key governance and financial attributes; legal matters complicate things further.

Operations: There is clearly a case for MTR’s ability to make existing operations improve efficiency; the Wall Street Journal article notes that London’s Overground went from 88.4% on-time to 96.7% after a few years of MTR-led operations. Clearly, you can export the expertise to make the trains run on time.

The rail network itself is not particularly expansive – 108 miles of heavy rail, 84 stations, first operating in 1979; not all that different in scope from DC’s Metrorail system of 106 miles and 86 stations (prior to the opening of the Silver Line) first operating in 1976. Yet the MTR sees 4.5 million daily riders, compared to Metro’s modest 780,000.

The Checkerboard Hill blog (named for the old visual marker on the nasty approach to the old Kai Tak airport) provides a nice overview of the MTR system, complete with a link to a track diagram.

Finances: MTR Corporation operates the rail system, owns and develops real estate around stations, and contracts with other entities to build and operate transit systems around the world. The corporation is 76% owned by the Hong Kong government, with shareholders owning an increased share of the company since an IPO in 2000.

Popular myth holds that MTR is only profitable due to real estate investment, but that is easily dispatched with a quick glance at a financial statement shows operating profits on transit operations (the aforementioned 186% farebox recovery ratio) as well as real estate.

An exported version of MTR can directly control operations and make the trains run on time, but they won’t always have direct control over adjacent development. Nonetheless, it’s worthwhile to look at their success. Even without profits from real estate development, MTR’s development plans serve the key role of ensuring transportation investments are paired with supportive land uses. The Atlantic puts it this way:

Like no other system in the world, the MTR understands the monetary value of urban density—in other words, what economists call “agglomeration.” Hong Kong is one of the world’s densest cities, and businesses depend on the metro to ferry customers from one side of the territory to another. As a result, the MTR strikes a bargain with shop owners: In exchange for transporting customers, the transit agency receives a cut of the mall’s profit, signs a co-ownership agreement, or accepts a percentage of property development fees. In many cases, the MTR owns the entire mall itself. The Hong Kong metro essentially functions as part of a vertically integrated business that, through a “rail plus property” model,  controls both the means of transit and the places passengers visit upon departure.  Two of the tallest skyscrapers in Hong Kong are MTR properties, as are many of the offices, malls, and residences next to every transit station (some of which even have direct underground connections to the train). Not to mention, all of the retail within subway stations, which themselves double as large shopping complexes, is leased from MTR.

Payton Chung digs into the numbers on MTR’s retail-heavy revenues:

55.4% of MTR’s total 2012 profits stemmed from property and in-station commerce: 36.1% from rents and management income and 19.3% in for-sale development. Profit margins on the property businesses are certainly healthy: 81.6% on investment property and 89.2% on in-station commercial, vs. 46.1% on Hong Kong transport and just 4.7% on the emerging international transport businesses. A near-90% margin practically qualifies as minting money. (In fact, it’s much better than minting money: the U.S. Mint cleared only 21% seigniorage on circulating currency in 2012.)

Note that in-station commercial offers the richest margins; over half of this business unit’s revenues come from in-station retail, with the rest from advertising and telecom fees within stations. MTR collected US$276.4 million on 608,729 square feet of in-station retail, for an unbelievable-for-the-US (but not for HK) average rental rate of $454/foot, well over twice the rents garnered per foot of investment property above the stations. Averaged across MTR’s 84 heavy-rail stations, that’s 7,247 square feet of retail per station.

This kind of in-station retail isn’t dependent on the kind of development rights seen elsewhere in the MTR system (though other cities might will certainly struggle to meet that ‘unbelievable for the US’ rent without Hong Kong-like density). Some in-station retail isn’t that different from examples around the world; making better use of empty spaces fronting streets in stations and under viaducts.

Street-facing retail spaces beneath the station mezzanine. Image from Google Maps.

Street-facing retail spaces beneath the station mezzanine. Image from Google Maps.

Other examples are internal to the station, and not different in concept from small-scale retail you’ll find in a shopping mall or at an airport:

Mezzanine level retail spaces in MTR's Kowloon Bay station. CC image from Wiki.

Mezzanine level retail spaces in MTR’s Kowloon Bay station. CC image from Wiki.

MTR’s practice of intense and extensive development around stations ensures maximum linkage between the investment in high-capacity transit and the land use to support that investment. Land is leased to MTR at pre-rail values (all land is owned by the government). This extends beyond just TOD; it represents the full integration of transit planning and development. The corporation both captures value created by the transit system, but also earns a long-term source of revenue to augment the system’s operational revenues.

Current US practice for TOD and joint development is barely integrated by comparison. Too often, the transportation-only focus (and a healthy dose of auto bias) leads to extensive park and ride lots rather than dense development around stations. Where dense development does happen, the transit agency isn’t always a direct beneficiary. Speaking to an audience at Harvard’s Kennedy School (as reported by Capital New York), MTR CEO Jay Walder put it in terms of financial sustainability:

“If the infrastructure is not self-sustaining, then the reality is that it cannot rely on public funding always being there,” Walder said Thursday, at Harvard’s Kennedy School. “At some point politics simply diverts the money elsewhere. And you might say it doesn’t have to be that way, but that’s just the reality of the case.”

In Hong Kong, the independently run MTR Corp. buys the land adjacent to future rail lines from the government at pre-development prices and then, once the line is built and the land alongside developed, captures the growth in value of that land and uses it to fund rail operations.

“In that way, the increase in the value of the property becomes a proxy for the broader public benefit and aligns the financial basis with the societal benefit that is being created,” said Walder. “And it also ensures that subject to normal business risk … that the corporation has the proper resources not just to be able to build a rail line, but also to be able to operate it, maintain it and renew the systems and equipment over time.”

Speaking of New York’s Second Ave Subway, Walder has no doubt it “will create a tremendous amount of value,” but that within the current financing scheme “we don’t have any mechanism to capture that back.”

Proxies for such integrated transit and development might include models we see in the US already, such as TIF or other special assessments to finance new infrastructure with development revenues. Yonah Freemark argues there might be a “residual fear” of urban renewal in allowing a public agency to directly develop real estate. Likewise, backlash against the use of eminent domain for economic development might torpedo integrated TOD before it gets started. It’s one thing to re-develop existing parking lots or air rights above key rail yards and other infrastructure, but the politics of land development and property rights will be difficult in the US.

Governance: Other elements of the MTR model (transit plus development) aren’t anything new to the US. Plenty of transit operators in the US also historically developed land to provide riders to their systems (or, on the other side of the coin, built transit to improve the access to their land). Privatized transit operations isn’t a new idea either. However, the current US system of public agencies and authorities operating transit isn’t set up to take advantage of land development around stations.

There are plenty of examples of successful land use intensification around stations; Metro’s Orange Line in Arlington, VA stands out. However, Metro did not develop any of that land. Joint development agreements for private sector developers to make use of WMATA land returns marginal rent to the system, despite huge increases in value from the presence of the system.

MTR’s corporate structure allows the company the autonomy to build a development team capable of delivering world-class real estate projects; current transit authorities would not have the expertise to develop real estate. While the government owns a majority of the corporation, it is publicly traded and has access to capital markets for both real estate and transit projects often unavailable to existing authorities.

As noted in the discussion of finances and land use, none of this is new for transit in the US. However, associating that kind of development with government agencies or public authorities would be new ground.

Planning: Emulating MTR’s operations is one thing; it still doesn’t guarantee the kind of ridership success seen on the MTR system. Hong Kong’s geography is well suited to efficient transit; high-density, compact development built among a series of geographic choke points (mountains, water bodies) that offer an opportunity for transit to gain an edge on other transport modes. These same principles apply elsewhere, but likely to a lesser degree.

Metro’s stainless steel future – Rosslyn

As the construction fencing starts to come down around the second entrance to Rosslyn Station, you can now see the future aesthetic for Metro infrastructure. Lots of steel and glass, but little of Metro’s original materials: concrete, tile, and brass.

Elevator-only second entrace to the Rosslyn Station. Photo by the author.

Elevator-only second entrance to the Rosslyn Station. Photo by the author.

The three elevators descend to a new mezzanine adjacent to the existing mezzanine. More renderings of the project are available at Arlington County’s website.

Cutaway of the Rosslyn Station second entrance. Image from Arlington County.

Cutaway of the Rosslyn Station second entrance. Image from Arlington County.

Above ground, the elevators emerge in a completely different structure across the street from the existing entrance. The separation between the two avoids the discord between Metro’s current embrace of stainless steel and the system’s historic colors and materials. Even though this project represents an addition to an existing station, the construction is almost entirely outside of the existing station shell. Unlike the proposed Bethesda renovation, the Rosslyn project thereby avoids the conflict between the old and new palates.

New Rosslyn Station entrance pavilion. Photo by the author.

New Rosslyn Station entrance pavilion. Photo by the author.

As the Metro system has expanded, it’s also picked up architectural variety. Even during the build-out of the original Adopted Regional System, the station architecture varies from station to station, depending on age and the construction methods. All of the ARS stations used the same palate of materials, despite the variety in design. Additions beyond the ARS (NoMa infill station and the Largo Extension) feature a different look than other above-ground stations; the Silver Line to Dulles will feature an entirely different architectural vocabulary.

Speed, urban transportation and geometry heuristics

Following up on this previous post, noting that “transport is mostly a real estate problem” – a few quick heuristics on cities, speed, and space:

Comparison of population/employee density and street area per person. Image from NYU Urbanization Project.

Comparison of population/employee density and street area per person. Image from NYU Urbanization Project.

Regarding speed: 

Speed requires space; faster travel occupies a larger area than slower travel.

Speed alters our perception of space. Faster travel makes large things seem smaller (hat tip to this post from GGW for the links). The properties of the space affect how we use it and what we percieve it to be; wider roadways within streets get used for faster travel.

Regardless of speed, cars require large spaces relative to their capacity. Even when parked (v = 0), cars require lots of space. By extension, building cities around requires a completely different spatial footprint.

Regarding space: 

There is a strong tendency for cities to devote about 25% of their land to streets. Street networks are for mobility, but also for access to land. Devoting too much land to streets is wasteful; too little makes it difficult to unlock the value of the land within a city.

Intersection density correlates with walkability and connectivity; wider instersection spacing correlates with the higher speed travel of cars.

Consider the relationship between the density of the network (intersection density), the tendency to use ~25% of land for streets (regardless of the density of the place), and street width on the kind of transportation.

Simply requiring some minimum intersection density for new developments via a code will still be subject to ‘gaming’ and open to unintended consequences.

Street networks are sticky and tend not to change once established; the cities that grow around them are path-dependent. However, transport networks can be layered – subways travel fast, require space and grade-separation, but deliver passengers to the street grid as pedestrians; just as freeways are layered above/below streets and deliver high volumes of cars to local streets.

While the physical space allocated to streets tends not to change, the use of that space can change a great deal over time.

A visual survey of selected elevated rail viaducts: part 5 – Vancouver and Tysons Corner

Pulling together some suggestions from the comments of the series prologue, part 1part 2, part 3, and part 4

Vancouver: Alon Levy reminds us to look at Skytrain’s viaducts in Greater Vancouver. Skytrain represents the kind of future for rapid transit this series means to investigate, baked right into the system’s name: expansion of transit aboveground, rather than under.

Skytrain’s fully automated, fully grade-separated network includes underground transit in dense areas and along narrow streets, but makes extensive use of elevated rail along wide streets and freight rail rights of way (active and dormant). Jarrett Walker discusses the virtues of the Skytrain system, above and beyond that of regular rapid transit – with the automated trains allowing for increased frequencies without increasing the associated operating costs:

Light rail is wonderfully flexible, able to run onstreet with signalized intersections, and across pedestrian zones, as well as in conventional elevated or underground  profiles.  Driverless metro must be totally grade-separated, which in practice usually means elevated or underground.  SkyTrain got its name because the original lines were mostly elevated, though the newest, the Canada Line, has a long underground segment.

The system’s most recent addition, the Canada line, features elevated sections for the two southern branches – one that goes to the airport, and one to redevelopment areas in Richmond.

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Skytrain Canada Line viaduct over a sidewalk in Richmond, BC. Image from Google Maps.

By placing the line alongside the roadway when next to surface parking, they’ve managed to expand the sidewalk without imposing too much on the pedestrian environment. The benches and trellises around the columns are a nice touch. The single guideway for both tracks helps minimize the bulk of the guideway. When those parking lots are redeveloped, they can front on the sidewalk without overshadowing it.

Aerial view of Skytrain in Richmond, BC - showing redevelopment of suburban land uses. Image from Google Maps.

Aerial view of Skytrain in Richmond, BC – showing redevelopment of suburban land uses. Image from Google Maps.

Older elevated guideways in the system include center running sections through suburban land uses:

Center running elevated Skytrain line. Image from Google Maps.

Center running elevated Skytrain line. Image from Google Maps.

Some sections run along alleyways.

Aerial of alley-running aerial alignment. Image from Google Maps.

Aerial of alley-running aerial alignment. Image from Google Maps.

Other sections combine separate and adjacent right of way with berms and greenery:

Elevated rail shielded by trees. Image from Google Maps.

Elevated rail shielded by trees. Image from Google Maps.

Center-aligned side-platform station. Image from Google Maps.

Center-aligned side-platform station. Image from Google Maps.

Vancouver provides lessons for rapid transit expansion in that it uses elevated rail through suburban-style rights of way.

Tysons Corner:

The Silver Line extension of Washington’s Metro system to Tysons Corner follows some of same principles as Skytrain, but without the same quality of execution. Part of the challenge is the landscape (Tysons features some wider roads than Richmond), and part is in the transit infrastructure.

View of Tysons guideway along Route 7 in Tysons Corner. Image from the author.

View of Tysons guideway along Route 7 in Tysons Corner. Image from the author.

Tysons tunnel proponents claimed that a Spanish-style large-bore TBM could tunnel through Tysons at lower cost than elevated rail. The authorities rejected this argument after some study, and with good reason. It may be true that the Spanish can build transit tunnels extremely cheaply (they can!), but it makes little sense to compare American elevated costs with Spanish tunneling costs.

Instead, it’s illustrative to look at relative costs of construction types. If the contractors could’ve built tunnels at the same cost as the Spaniards, they could’ve built elevated rail for less money, as well.

View of Silver Line Metro, looking back towards Greensboro Station. Image from the author.

View of Silver Line Metro, looking back towards Greensboro Station. Image from the author.

Along Route 7, they’re starting to install sidewalks, but the pedestrian environment is still lacking.

View of new sidewalk along Route 7, leading to Greensboro Station. Image from the author.

View of new sidewalk along Route 7, leading to Greensboro Station. Image from the author.

There are opportunities for infill development along these new sidewalks, but sidewalks adjacent to a high-speed stroads isn’t the most compelling environment. Other new transit-oriented development in Tysons isn’t attempting to turn the existing main stroads (routes 7 and 123) into nice streets, but rather add a pedestrian layer on top of the current auto-centric network.

Image from the author.

Image from the author.

Image from the author.

Image from the author.

Table of contents:

A visual survey of selected elevated rail viaducts: part 3 – Els that gave Els a bad name

For more, see the series prologue, part 1, and part 2

A look at some of the Els that gave Els a bad name:

Chicago: The city’s rapid transit system’s elevated lines are ubiquitous; the system is named for them. In the Loop, the Els run above city streets. In other parts, some Els run above alleyways or private rights of way, away from streets:

Chicago El over an alley. Photo by author.

Chicago El over an alley. Photo by author.

Under the Chicago El. Photo by the author.

Under the Chicago El. Photo by the author.

Chicago El 1

Intersection of Wells and Lake in Chicago. Image from Google Streetview.

Owing to both the size of the structure, the relatively narrow streets, and the enclosure provided by the buildings, the Els loom over Chicago’s streets.

Adams/Wabash Station. Image from Google Streetview.

Adams/Wabash Station. Image from Google Streetview.

To be fair, most of these Streetview images are from directly under the structures, while many of the others are views from the side. Part of this is due to the street width, and part due to the buildings fronting the street. If you were looking for examples of suitable elevated viaducts for retrofitting suburbia, or for less dense urban neighborhoods, this isn’t a great example. Nonetheless, as noisy and obstructive as the Els can be, you can still find light and air above the sidewalks:

Intersection of Monroe and Wabash, Chicago IL. Image from Google Streetview.

Intersection of Monroe and Wabash, Chicago IL. Image from Google Streetview.

Philadelphia: The number of American cities with legacy heavy rail transit systems (meaning pre-war) is fairly limited (Boston, New York, Chicago, and Philadelphia). Over the last decade, Philadelphia reconstructed most of the Market St elevated, replacing Chicago-style structures with a single pier supporting a steel structure:

Market St El, prior to reconstruction, CC image from connery.cepeda

Market St El, prior to reconstruction, CC image from connery.cepeda

Market El, reconstructed:

Finishing work on the reconstructed El. Image from Google Streetview.

Finishing work on the reconstructed El. Image from Google Streetview.

On the other side of Center City, the El above Front Street almost reaches from building face to building face along Philadelphia’s narrow streets:

Elevated rail above Front St. Image from Google Streetview.

Elevated rail above Front St. Image from Google Streetview.

Boston: Much of the post-war transit investment in Boston focused on re-arranging infrastructure, tearing down Els and replacing those lines with subways. Few elevated sections remain, such as this portion of the Green line near Lechmere Station:

Green Line El near Lechmere Station. Image from Google Streetview.

Green Line El near Lechmere Station. Image from Google Streetview.

Perhaps the only reason this portion survives is because it’s directly attached to a river crossing:

Aerial view of Boston from Google Maps.

Aerial view of Boston from Google Maps.

Table of contents:

A visual survey of selected elevated rail viaducts: part 2 – best practices of integrating viaducts into urban designs

Continued from the prologue and part 1… A look at legacy examples of older elevated construction precedents. Some examples drawn from this post and this thread on the archBoston forums.

Berlin: As a part of his writing about elevated rail, Jarrett Walker takes note of Berlin’s elevated rail, and the use of space beneath them:

But the Stadtbahn is something else.  Completed in 1882, it runs east-west right through the middle of the city, with all kinds of urban land uses right next to it.  It’s a major visual presence in many of Berlin’s iconic sites, from affluent Charlottenberg to the Frederichstrasse shopping core to the “downtown of East Berlin,” Alexanderplatz.  It even skirts Berlin’s great central park, the Tiergarten, and looks down into the zoo.  If you were proposing to build it today, virtually every urbanist I’ve ever met would instinctively hate the idea, and if the idea somehow got past them, the NIMBYs would devour it.

Yet much of it is beautiful. Most of the viaduct is built as a series of brick arches.  Each arch is large enough to contain rooms, and today many of these are retail space, most commonly restaurants.  These restaurants put their tables outside, sometimes facing a park but still, unavoidably, right next to the viaduct, and they’re very pleasant places to be.  A train clatters overhead every minute or two, but it’s not dramatically louder than the other sounds of urban life, so it’s a comfortable part of the urban experience, devoid of menace.  I could sit in such a place for hours.

Indeed, the  four-track Stadtbahn cuts through Berlin on its own right of way, not in adjacent to or in the median of another street. Many streets run tangent to the elevated railway for segments, but much of the city directly abuts the railway.

Berlin Stadtbahn aerial image from Bing Maps.

Berlin Stadtbahn aerial image from Bing Maps.

By cutting through the city on a separate level and without directly mirroring the street grid, the transit network adds another layer to the cityscape. The city, both old and new (and yet to be built), has grown around the elevated rail:

Berlin Stadtbahn aerial from Bing Maps.

Berlin Stadtbahn aerial from Bing Maps.

At the street, many of the viaduct’s archways have been turned over to retail uses, activating what would otherwise be a barrier of dead space:

View of the same viaduct from street level. Image from Google Streetview.

View of the same viaduct from street level. Image from Google Streetview.

Jarrett’s post features a number of other images from Berlin, showing the various types of spaces the Stadtbahn creates. He closes asking if we might learn from these legacy examples in building new transit infrastructure:

Europe has some really beautiful transit viaducts, including some in the dense centres of cities.  Most of them are a century old, so the city has partly grown around them.  But the effect is sometimes so successful that I wonder if we shouldn’t be looking more closely at them, asking why they work, and whether they still have something to teach us about how to build great transit infrastructure.

Paris: Metro Line 6:

Paris Metro Line 6. Image from Google Streetview.

Paris Metro Line 6. Image from Google Streetview.

Line 6 runs down the middle of several wide streets, providing enough room for bike and pedestrian pathways beneath the viaduct, while also leaving enough space alongside for trees and landscaping. The aesthetic elements of the rail infrastructure (stone piers, steel spans) echo the architecture of the city as a whole.

Paris also has examples of old, now un-used vaiducts re-purposed as part of a vibrant cityscape:

Paris 2

Viaduc des Arts, Paris. Image from Google Streetview.

Above the viaduct is now an elevated linear park.

New York: In the comments of Part 1, Charlie asked about New York’s High Line. I did not initially include it, but I do think it offers an intersting example. The High Line (or what remains of it), like Berlin’s Stadtbahn, does not run directly above many streets. Also, the city grew around the infrastructure – in the High Line’s case of delivering freight to adjacent factories, that direct interaction was the very point of building the line.

Aerial view of the High Line weaving between and through buildings. Image from Google Maps.

Aerial view of the High Line weaving between and through buildings. Image from Google Maps.

Southern end ot the High Line, running adjacent to Washington St. Image from Google Streetview.

Southern end ot the High Line, running adjacent to Washington St. Image from Google Streetview.

One particular example of elevated rail in New York both looks to the past (we don’t build ’em like we used to) but could also learn from the repurposing of the spaces created under viaducts for uses other than storage. The Queens Boulevard elevated rail line runs down the middle of a wide street, with large archways beneath the tracks – currently used for parking.

New York - Queens Blvd 1

Queens Boulevard elevated rail. Image from Google Streetview.

Consider that when the line was built, the surrounding area was completely undeveloped. The city (and the roadway) emerged around the rail line, rather than cutting the rail line through an existing urban evironment (I don’t know that any single image better conveys the links between transportation, land use, and development). Meshing transit expansion into low-density areas is not just about transportation, but about re-shaping the city. Under the right conditions, it can work well.

New York has other examples of repurposing space beneath viaducts. While not specifically a transit example, the re-use of space under the Queensboro Bridge approaches in Manhattan is an example of what’s possible with some of these rail viaducts:

Queensboro bridge approach, New York. Image from Google Streetview.

Queensboro bridge approach, New York. Image from Google Streetview.

Short of re-purposing the space beneath the tracks, the Queens Boulevard elevated rail allows for a perfectly acceptable kind of rail, without shadowing the streets or sidewalks below, making use of the street’s wide right of way. Alon Levy takes note:

But when there is an el about Queens Boulevard, everything works out: the street is broken into two narrower halves, with the el acting as a street wall and helping produce human scale; the el is also farther from the buildings and uses an arched concrete structure, both of which mitigate its impact.

Any other examples of older elevated infrastructure we can learn from?

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